1. The Field of the Invention
This invention relates to air propulsion devices for surface craft and more particularly to that class which is adapted to be installed thereon without employing permanent mounts affixed to the craft to accommodate the propulsion motor.
2. Description of the Prior Art
The prior art, in the main, concerns fastening the air propulsion motor to the transom or rear wall of a boat. U.S. Pat. No. 2,987,281 issued June 6, 1971 to R. K. SCHURR et al teaches a clamp having a lead screw that provides pincer-like forces to the area adjacent the topmost edge of a transom. The air motor is secured to the clamp mechanism through pivot means such that the blade producing the propulsion air currents can have its axis rotated from side to side, permitting thereby, steering-like forces to be imparted to the vessel to which the assembly is attached. U.S. Pat. No. 1,180,430 issued Apr. 25, 1916 to C. E. PIEDEL shows a similarly equiped assembly having a lateral platform below the motor about which the motor assembly and blade mounting shaft is permitted to pivot. U.S. Pat. No. 3,791,333 issued Feb. 12, 1974 to J. D. LOSCH also shows a propulsion device adapted to be mounted to the rearmost wall of a surface craft, teaching a novel design for the blade. There appears to be no known method heretofore that simply and easily adapts to boats of varied designs and shapes allowing for the mounting, in temporary fashion, of an air propulsion device to other than the transom. Some craft cannot accommodate the size and weight of this form of propulsion on locations other than attachment astern of amidships and forward of the stern proper. Transoms, though designed to securely support outboard engines may not possess the strength capable of adequately supporting the motor as well as vibrating blades suspended a substantial distance above the uppermost edge. The weight of the engine as well as the center of the blade being located substantially above the transom tends to cause the vessel to yaw nose upwards when not in motion. Since the craft may be employed in very shallow water, it is highly desirable to maintain the hull at substantially a horizontal position at all speeds. Locating the propulsion unit at any desired point along the vessel length provides complete flexibility for a single apparatus adapted to be utilized with a variety of craft shapes and sizes.